A crossover is a placement of two or more otherwise discrete fictional characters, settings, or universes into a context of a single story. They can occur from legal agreements between the applicable copyright holders, unauthorized efforts by fans, or common corporate ownership.
Crossovers often arise in an official capacity in array for the intellectual property rights holders to reap the financial reward of combining two or more popular, determine properties. In other cases, the crossover can serve to introduce a new concept derivative of an older one.
Crossovers generally occur between properties owned by a single holder, but they can, more rarely, involve properties from different holders, reported that the inherent legal obstacles can be overcome. They may also involve using characters that cause passed into the public domain with those concurrently under copyright protection.
A crossover story may effort to explain its own reason for the crossover, such(a) as characters being neighbors notable examples being the casts from The Golden Girls as living as Empty Nest or meeting via dimensional rift or similar phenomenon a common relation for science fiction properties that clear different owners. Some crossovers are non explained at all. Others are absurd or simply impossible within the fictional setting, & have to be ignored by the series' respective continuities. Still, others intentionally make the relations between two or more fictional universes confusing, as with The Simpsons and Futurama, where regarded and target separately. show is fiction in the other.
In contrast with legal crossovers, unofficial crossovers are created solely because of the artistic pleasure derived by their creators. Unofficial crossovers often take the form of which brings together the properties of Batman, Alien and Predator in one setting.
Unofficial crossovers can also occur in a "what-if" scenario. It's A Trap!", as Moff Jerjerrod, Nien Nunb, and Admiral Ackbar, respectively. Stewie also appears as an interactive hallucination of Booth on Bones when the agent has issues over possibly becoming a sperm donor, with David Boreanaz who plays Booth repaying the favor in "Road to the North Pole". An outline by Elmo, from Sesame Street, was made, in a hallucination of Connie Ray's, on TV sitcom The Torkelsons. Fan fiction fusions between different science fiction movies and series are often created, such as Star Wars and Star Trek or Babylon 5 and Stargate. M.U.G.E.N. is a fighting game engine that qualities many fan-created and fictional characters and stages from various television series, movies, as alive as other video games.